No Road Trips for Toyota's i-unit

November 20, 2005

A press of the palm starts up the rear-wheel-drive engine. Digital tunes are a couple of joystick clicks away. And there are no side mirrors to adjust -- sensors detect any objects approaching from behind. Despite these unconventional systems, handling Toyota's latest i-unit prototype in a test drive proved easier than expected. Not that I was intimidated by the horsepower -- the top speed is around 25 miles per hour -- but the futuristic model gives a whole new perspective to the term motor vehicle.

Toyota (TM) says it designed the i-unit to evoke a tree leaf, which it calls "the most simple thing in nature," but to my eye, the electric-powered one-seater looks like a cross between a jet pack and a La-Z-Boy recliner on wheels. The prototype is a showcase for automotive applications of "drive-by-wire" engineering and information technology, with a dose of zero-emission environmentalism thrown in.

Individually, none of its technologies is new. What makes the i-unit stand out -- in addition to its odd silhouette -- is the seamless integration of all three systems into one vehicle.

Toyota officials hint that the prototype may eventually graduate to full-scale commercial production -- though they won't specify any time frame. "From a technical point of view, we are quite close to being able to [mass] produce," says Yoshiaki Kato, executive chief engineer of the i-unit project at Toyota's Advanced Development Dept.

Don't expect to see it soon on eight-lane superhighways, though. More realistic applications include use in retirement homes, gated communities, or even on the golf course.

REINVENTING THE STEERING WHEEL. So far, Toyota has manufactured about 40 i-units. After wowing crowds at the World Expo in Japan this summer, an updated version of the vehicle recently debuted in the U.S. I was invited to a special demonstration at a Toyota dealership in Manhattan, where I kicked the tires and gave it a whirl around the showroom.

The biggest challenge is getting used to driving without a steering wheel, foot pedals, or dashboard. You pilot the i-unit by manipulating an orb-like controller at the tip of the right-hand armrest. It controls direction, speed, and braking with a tug up and down or by twisting it left and right.

Those commands are relayed electronically to independent motors attached to the left and right rear wheels. The click-wheel controller on the opposite armrest starts up the vehicle and handles audio and visual functions. In lieu of rear-view mirrors, a thin fiber optic cable embedded along the rim of the transparent hood reflects LEDs that flash brightly whenever an object detected by one of six mini-cameras approaches from the rear or side.

HITTING THE STREETS. The i-unit can be driven in two different configurations, selected with the push of a button. In its upright mode, the vehicle's four wheels are positioned close together. That is ideal for slower speeds because it enables you to keep eye level with another person walking to the side. For faster speeds, the front wheels jut out and the seat reclines. This "dune buggy" mode increases the aerodynamic profile and lowers the center of gravity for greater stability.

Despite all the gizmos, driving the i-unit is remarkably intuitive. Following a 30-second briefing I was cruising around effortlessly, steering clear of parked Highlander SUVs and Corolla sedans. I briefly toyed with the idea of zipping out of the showroom and into Manhattan traffic, but thought better of it. For one thing, the i-unit's flimsy transparent head shield and the roller coaster-like parts that substitute for a seat belt would provide little protection from an oncoming V8-powered SUV.

INTELLIGENT DESIGN. For street use, Toyota proposes plugging these vehicles into an Intelligent Transportation System that would automate much of the driving experience. A carefully controlled small-scale ITS system designed for the i-unit was demonstrated at the Aichi Expo. But while similar systems have been tested in the U.S., they are not likely to become reality anytime soon.

Not only is the i-unit a bit flimsy for commercial roadways, it is also severely limited by a 30-minute battery life before it needs recharging. That speaks to a larger issue involving the snail-like pace of progress in battery technology, a problem affecting all electric vehicles. The true tests will be determining how much of a market there is for these vehicles and whether the profit margin justifies the expense, which Toyota only says will be less than the cheapest compact cars today.

Judging from the success of hybrid gas-electric cars such as the Toyota Prius, however, some people seem willing to pay a premium for a set of eco-wheels. The i-unit is made almost entirely of bio-plastics and composites derived from corn, sugar cane, and the African kenaf plant. And because it is entirely electric, the i-unit emits little more than hums and whirs.